Apparatus for applying elastic covers



June 12, 1945. v v. AH. HASSELQUIST' 2,378,011

APPARATUS FOR APPLYING ELASTIC COVERS Filed oct. 2. 1944 `2 sheets-sheet 1 June l2, 1945'.

VL H. HAssELQUlsT APPARATUS FOR APPLYING ELASTICv COVERS Filed Qct. 2,y 1944 Patented June 12, 1945 l APPARATUS FOR APPLYING' ELAST o f i COVERS The B. F. Goodrich Company', a corporation of New .York

New York; 351.1., p

Application october `2, 1944, .serialincifssasw 1o ciaims. roi. 25455145', f

This invention relates to apparatus forstretching elastic covers about surfaces, and is especial- 1y useful for applying ice-removing and lother protective coverings to the surfaceiof airfoils.-

A*Elastic ice-removing covers have been secured about the` leading edges of wings and'other airfoils by rows of hollow .tubular rivets secured to the skin of the airfoil and having threaded bores for receiving screws. Thecovers have been provided with rows of apertures along their margins forl receiving fastening screws adapted to enter the threaded bores of the rivets,fand fairing stripsof sheet material, also having apertures iol' fory engaging the same screws sometimesl have been applied over the margins of the covers. ff.,

Stretching of the covers lto secure them in place under tension without damage to the covers or to the' surfaces to be covered'has `been a dimcult problem, especially where the parts areof'large size. Where -ice removing covers are to be' applied l these have often had air connections integral therewith which had to be insertedv through apertures therefor in the skin of the 'airfoiL causing further difficulties of assembling. By the present invention an improved apparatus is provided for facilitating the assembling operation.v

' Objects of the present invention are to lprovide for preliminarily stretching the entire cover so as to -position properly the airconnections and then applying the coverabout4 the leading edge of the airfoil in uniformly stretched condi` tion, to provide for permitting application of one margin of the cover in advance of entry of the air connections, to provide for application of the covering at any position or attitude of the air-L the least;amount`y foil, and to apply the cover with of manual exertion.

These and other objects will appear yfror'ntlie drawings.

Of the drawings,

following description and Athe accompanying F'ig. 1 is a plan view of the leading edge portion I.

of an airfoil, a covering in the initial position of stretching and stretching apparatus attached thereto made in :accordance with vandhembodyi'ng the invention, parts being broken away., y .4

- Fig. 2 is a cross section of the Lsaine, taken on lineZ-Z of Fig. 1.

Fig. 3 is .a similar cross 'sectional view showing I the covering stretched to final positionand in dot-andl-,dash lines indicating n intermediate position of the covering and apparatus;L

f Fig. 4 is a view thereof taken online 4--4-.of l

, 1 I Y v 5,5

Fia 3- lock,

Referringtorthe' drawings, the numeral I0 designates a leading edge portion of an airfoil tov whchan ice-removing covering' Il of elastic material is to be secured; i The covering isformed with 'inatable'char'nbers I3, I4, l5 communicating with tubular connections IB, I1, I8. For securing` the covering in place, tubular internally threaded rivetsl 9 are secured in apertures thereforfinthe" skin fof the airfoil and corresponding in location with one margin Ila of the covering, the rivets being arranged. in spaced-apart relation spanwise' along the airfoil, and corresponding'iy arranged apertures 20 for receiving'secur- 'formed in the margin ofthe ing screws 2i are covering.` l f The opposite margin ofthe covering is also provided with spaced apart apertures 30 for` receivinglfasteningscrews 3| and the airfoil is formed with correspondingly spaced apertures 32 with-hollow internally threaded rivets '33 secured" therein for receiving the. screws 3l. The rows ofrivets I8 and" 33 are spaced chordwise about the airfoil in such manner as to require the cov-` ering to be stretched when in place. Fairing strips-of metal, such as 34, may be secured over the margins of the covering'.

For receivingvthe connections I6, il, `I 8, suit- -able`through apertures 35, 36, 31 are formed inV the skin-of the airfoil.

-For stretching the covering for securing it toy the airfoil, straps 45 having Aan aperture 46 in one end and a'Uk-shaped crotch 41 formed at the .opposite end'are secured at intervals along the` airfoilil by `means of screws entering the hollow rivets 33.` 'A pipe or othervbar 48 is placed in the crtches of thejstrapsadjacent the surface of the airfoil,I andis secured in place by pins 49 inserted' in apertures of the arms of the'crotch. One or Amore strut members, depending upon the length of the covering spanwiseof the airfoil;` isfulcrumedon thebar 48, the strut mem- 1 bers being each providedwith a crotched end 5i l for engaging over the bar 48 so as to be rotatably i positioned-thereabout.' Each strut has a block 52 slideablyf mounted thereon. Crossv apertures 53 are formed in each block for receiving a bar 54 parallell to bar 48. That portion of each block 52 in which the'aperture 53 is located is arranged to iprojectaxially of the strut beyond the portion ,l

embraein'gzthestrut providing clearance for the bar -48,.f.fwhenthe,strut is rotatably positioned thereabout'inl the opposite direction, as in Fig. 3. A series of hooks 55 are adapted to engage over 5 isza'detail view of the slide showing the n -said guide adapted to frictionally engage said strut to lock said guide against movement along said strut in. a direction toward said bar, said moveable member being displaceable to permit movement in such direction.

9.7Apparatus for stretching an elastic covering having a row of apertures along a margin thereof into aposition overl a row of securing apertures of an aircraft surface while an opposite margin of the covering is restrained 1 against yielding with respect to said surface, said apparatus comprising a bar extending along the surface of the aircraft at the position of desired attachment, a strut having end engagement with said bar as a fulcrum, a `guide moveable along said strut, means on said guide for holding the rst said margin of the covering, said last named means being olset from said guide for positioning close to said bar by movement of said guide to align the apertures of said covering directly over said securing apertures, means for moving said strut about saidbar to tension the covering, and means on said guide frictionally engaging said strut to retain said guide` against movement along said strut toward said bar, said last-named means being displaceable to permit movement in such direction.

10. Apparatus asv defined in claim 9 in which the means frictionally engaging said strut comprises a self-energizing clutchv member engaging said strut and displaceable to permit movement' of said-guide therealong. t

VICTOR H. HASSELQUIST. 

